Modifications of synaptosomal Na+ -K+ -ATPase activity during vasogenic brain edema in the rabbit.

This study investigates the functioning of synaptosomal ouabain-sensitive Na+ -K+ -ATPase in cold-induced edema. During vasogenic brain edema development, the enzyme affinities for Na+ and K+ are progressively decreased paralleling the increase in the tissue water content, whereas maximal velocity of the reaction is not changed. On the basis of these data, it is likely that Na+ -K+ -ATPase impairment accounts for the intracellular uptake of water in this model of edema.